Trilobites ID in SD Wisconsin Grant Platteville Member?

[SteveRogers]

Hello! After losing 2020, and then winter, I was finally able to get out and look around in my new area, NE Iowa and near Grant County, Wisconsin. I walked down a few rivers in the Ordovician areas, Platteville Formation, Grant County, and picked up what I think might be a Trilobite? Based on the Various publications of the region, it may be Sceptaspis lincolnensi, but this is really my first Trilobite I have found (in many years of walking along looking at rocks) I haven't cleaned off any of the matrix, just a nice scrub. I also found this hash plate nearby, I liked the Gastropod? In the center and noticed and when I looked it may have a similar trilobite? Thanks, appreciate your help!

[ClearLake]

Welcome to the forum!  You certainly do have some trilobite parts there. The first rock has two pygidia on it, and maybe some other bits. I can’t confirm your ID from these pictures, but it looks like a possible match. You may want to pick at the matrix around the trilobites to see if you can expose more of it (if there is more) or at the very least to better see what is currently exposed. 

[Fossildude19]

I see 3 pygidia, and lots of other bits (possibly a cephalon) on the first rock. 

 

[Kane]

Looks to me fairly representative trilo-fauna, including Flexicalymene pygidia and some Isotelus fragments (including what may be a complete pygidium to the left of where Tim circled a Flexi at the top of the piece). 

[piranha]

 

There are too many axial rings and pleural ribs for Flexicalymene.

 

Ludvigsen, R., Chatterton, B.D.E. 1982

Ordovician Pterygometopidae (Trilobita) of North America.

Canadian Journal of Earth Sciences, 19(11):2179-2206  PDF LINK

[Kane]

Doh! Nice catch, @piranha! I should have looked closer. 

[SteveRogers]

Thank you all so much already! I will see about taking some of the matrix off. A few years ago I found an imprint of a Trilobite along a river in Milwaukee, but this is the first one I've found in 5+ years of fossil hunting in various places (not around here, obviously). 30+ years ago I got one of those bags of fossils with the yellow paper top for a Christmas present, and it sparked my interest in this hobby for a long time before I ever started looking - so finding Trilobite has been one of those back-of-my-mind goals for a very long time. Again, thanks!